Not all fossils are uncovered by digging in the dirt and breaking open rocks. While all fossils originate in various types of rocks, they can take a varied path before they reach scientists. An important example of this involves specimens housed in the Invertebrate Paleontology collections at The State Museum of Pennsylvania that were once part of a church near Altoona, Blair County, made from various rocks quarried and collected nearby.
Within these rocks were numerous fossils from the Shriver Member of the Old Port Formation, a rock unit that dates to the Early Devonian period, or just over 400 million years old, a time when Pennsylvania was under water. Many of these fossils were complete, such as this trilobite pictured above. Some individuals removed these fossils from the church. Fortunately, these specimens made their way to the North Museum of Nature and Science in Lancaster County and, then later, The State Museum.
Trilobites, ancient creatures that lived hundreds of millions of years ago, are some of the best-known fossil animals. They roamed shallow seas and oceans for approximately 270 million years. They have been found worldwide and many of their fossils have been discovered in Pennsylvania, as well.
During their time at the North Museum, these trilobite fossils were studied by Richard M. Busch and Frank M. Swartz. Eventually, the researchers determined that these trilobites represented a new type of animal, which they called Trimerus stelmophorus. These specimens typify the only fossils known from this animal and are some of the best preserved of this group anywhere in the world. They reveal to us how these animals lived and behaved. For example, trilobites had to shed their skin and grow new shells quickly, much like crabs do today, and these specimens help us understand that process.
This edition of Pennsylvania Treasures was written by Steven E. Jasinski, curator of paleontology and geology at The State Museum of Pennsylvania
About Pennsylvania Treasures:
The Pennsylvania Historical and Museum Commission houses artifacts hailing from all eras of the commonwealth’s past. These objects represent Pennsylvania arts, culture, history, sciences, business and agriculture. PHMC curators continue to research the stories behind many of these rarely exhibited artifacts and works of art. We are sharing these Pennsylvania Treasures with the public through weekly updates.